In the 13th century, the King of Sicily sought to discover the origin of language. Driven by this curiosity, he conducted an unethical experiment. In this experiment, several infants were placed in a room with foster nurses. These nurses only fed, bathed, and changed the infants, avoiding verbal interaction, emotional warmth, or any form of physical affection. The goal of the experiment was never achieved—tragically, all the infants died. Despite being regularly fed and changed, the lack of emotional and physical care is believed to have led to their deaths. While this brutal experiment failed in its original objective, it became one of the first documented psychological studies and revealed the vital role of skin-to-skin attachment (Solter, 2001).
Infants who experience skin-to-skin contact in early life show improved neurobehavioral outcomes such as physiological regulation, automatic capacities, better sleep, and reduced crying in the first six months of life (Browne, 2004). Recent studies highlight how skin-to-skin care contributes to the development of premature infants. Those who received fifteen-minute skin-to-skin sessions, three times a day for ten days, gained weight faster and left incubators six days earlier than the control group (Solter, 2001). Infants with increased skin-to-skin exposure from caregivers showed enhanced autonomic functioning (Jakubiak & Feeney, 2016) and a lower risk of physical health issues (Puig et al., 2013).
Thermoregulation is one of the most important physiological needs of newborns. A study showed that infants placed in incubators had body temperatures up to 1.5 degrees lower than those held against their mother’s skin (McKenna et al., 1993). Interestingly, when infants were held by their fathers, their body temperature increased significantly (Browne, 2004).
In one study, skin-to-skin contact with mothers significantly reduced pain responses during venipuncture (Olsson, Ahlsén, & Eriksson, 2015). Similarly, another study found that heel stick pain was alleviated through skin-to-skin contact (Gray, Watt, & Blass, 2000). Moreover, such early physical contact has been found to reduce existential distress (Cascio, Moore, & McGlone, 2018), lower stress responses even 10 years later (Jakubiak & Feeney, 2016), and increase skin hydration through higher evaporative loss compared to incubator care (Abouelfettoh et al., 2011).
Skin-to-skin bonding is essential not only for humans but also for animals. In non-human mammals, it plays a role in regulating survival-related behaviors (Tanaka, Kanakogi, & Myowa, 2021). Traditionally, psychologists believed infants formed attachments because mothers provided milk as a reward. However, psychologist Harry Harlow challenged this view in a groundbreaking experiment at the University of Wisconsin. He placed infant monkeys in a room with two artificial mothers: one made of wire that provided milk, and another made of soft terry cloth that did not. Surprisingly, the monkeys consistently preferred the cloth mother, indicating that comfort and physical affection were more important than nourishment (Solter, 2001).
Animal research also supports these findings. For example, brief separations of rat pups from their mothers resulted in increased maternal licking upon reunion, which helped reduce separation-related stress (Yoshida & Funato, 2021). Conversely, early disconnection led to psychological and behavioral abnormalities (Norholt, 2020).
High vs. Low Care & Attachment
Parenting quality in the first months after birth strongly influences an infant’s emotional and social development, forming the foundation for self-confidence and self-worth (Weatherston & Fitzgerald, 2010). Children raised in institutional settings—such as orphanages—often exhibit signs of reactive attachment disorder (Olatunji, 2019). In the 1940s, nearly one-third of infants in U.S. orphanages died despite adequate food and medical care, primarily due to a lack of emotional attention (Solter, 2011).
Researchers Sally Provence and Rose Lipton found that institution-raised infants had delayed motor development, showed less desire for social interaction, and exhibited lower levels of emotional expression compared to those raised by primary caregivers (Weatherston & Fitzgerald, 2010). A lack of physical touch during infancy can result in unusual behaviors, such as hair-pulling and speech disorders (Hertenstein, 2002).
Proximal parenting—characterized by close physical and emotional contact—is linked to increased compliance in children (Barry, 2019). Infants deprived of caregiver affection frequently develop sensory processing issues (Cascio, Moore, & McGlone, 2018). A study involving 24 adopted infants found that IQ levels correlated with the amount of verbal and physical interaction received (Beckwith, 1971).
Moreover, lack of care or overcontrolling parenting styles are associated with personality disorders such as anxiety and schizophrenia (Giakoumaki et al., 2013). Social touch in early life may also serve as an early indicator for autism spectrum disorder (Cascio, Moore, & McGlone, 2018).
Conclusion
Every infant requires emotional connection for healthy development, regardless of culture, ethnicity, or environment. This need for attachment is not limited to human beings; it is a universal biological imperative observed across species. Far from being a cultural construct, attachment theory reveals the profound influence of early emotional bonds on cognitive, emotional, and social development. It lays the foundation for mental health, resilience, and lifelong well-being.